This interaction between economic and political factors can explain important aspects of European integration. For instance, it can shed light on why Konrad Adenauer, the Chancellor of West Germany from 1949 to 1963, pushed for a geographically narrower but institutionally deeper customs union with France, Germany’s old enemy. Adenauer overruled his economic minister Ludwig Erhard, who was primarily interested in economic benefits and would have preferred a broader free-trade area, which France would have been unlikely to join given its own commercial and political interests (Garton Ash 1993; Moravcsik 1998